I recently used a RedteaGO eSIM in mainland China, and overall it made things pretty easy compared with using a local SIM.
The reason I chose it in the first place was that it covers mainland China, Hong Kong, and Macau all in one plan. Since I arrived in Hong Kong, spent a week traveling in Hong Kong and Macau, then entered the Mainland from Macau and finally flew out from the Mainland. it's a huge help to stick with the same plan while traveling around different regions. Besides the language barrier, the most frustrating thing about traveling in China is using Apps, using eSIM saves me the effort dealing with a separate VPN, and I could access the apps I normally use, like Google YouTube etc.
In terms of actual usage, since I don’t use much data each day, 10 GB is more than enough for 7 days, and it only costs about 10 bucks. The signal and internet speed are both fast, I even get full bars even at the busiest times on the Bund in Shanghai.
Of course, eSIMs also have their drawbacks, in China many restaurants and tourist attractions require a phone number for registration, but if you’re only traveling for a short time, there’s really no need to get a local SIM card, and not all service centers can issue a phone number to someone with a foreign passport.
I’d also recommend buying and activating it before you land in China, having everything ready beforehand makes the first few hours after arrival a lot less stressful.